Cleanly detach XHR and other pending loader clients from Inspector.

third_party/WebKit/Source/core/xmlhttprequest/XMLHttpRequest.cpp

 /*
  *  Copyright (C) 2004, 2006, 2008 Apple Inc. All rights reserved.
  *  Copyright (C) 2005-2007 Alexey Proskuryakov <ap@webkit.org>
  *  Copyright (C) 2007, 2008 Julien Chaffraix <jchaffraix@webkit.org>
  *  Copyright (C) 2008, 2011 Google Inc. All rights reserved.
  *  Copyright (C) 2012 Intel Corporation
  *
  *  This library is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU Lesser General Public
  *  License as published by the Free Software Foundation; either
@@ skipping 1076 matching lines @@
       DCHECK(!m_loader);
       handleRequestError(0, EventTypeNames::abort, receivedLength,
                          expectedLength);
     }
   }
   if (m_state == kDone)
     m_state = kUnsent;
 }
 
 void XMLHttpRequest::dispose() {
-  if (m_loader) {
-    m_error = true;
-    m_loader->cancel();
-  }
+  contextDestroyed(getExecutionContext());

[haraken, 2017/01/27 09:47:57]

I'd prefer not manually calling contextDestroyed (it should be called only by
LifecycleNotifer). Can we instead make contextDestroyed() call dispose()?

[sof, 2017/01/27 10:19:59]

ok, adjusted.

 }
 
 void XMLHttpRequest::clearVariablesForLoading() {
   if (m_blobLoader) {
     m_blobLoader->cancel();
     m_blobLoader = nullptr;
   }
 
   m_decoder.reset();
 
   if (m_responseDocumentParser) {
     m_responseDocumentParser->removeClient(this);
     m_responseDocumentParser->detach();
     m_responseDocumentParser = nullptr;
   }
 
   m_finalResponseCharset = String();
 }
 
 bool XMLHttpRequest::internalAbort() {
+  // Fast path for repeated internalAbort()s; this
+  // will happen if an XHR object is notified of context
+  // destruction followed by finalization.
+  if (m_error && !m_loader)
+    return true;
+
   m_error = true;
 
   if (m_responseDocumentParser && !m_responseDocumentParser->isStopped())
     m_responseDocumentParser->stopParsing();
 
   clearVariablesForLoading();
 
   clearResponse();
   clearRequest();
 
@@ skipping 669 matching lines @@
 }
 
 void XMLHttpRequest::suspend() {
   m_progressEventThrottle->suspend();
 }
 
 void XMLHttpRequest::resume() {
   m_progressEventThrottle->resume();
 }
 
-void XMLHttpRequest::contextDestroyed(ExecutionContext*) {
-  InspectorInstrumentation::didFailXHRLoading(getExecutionContext(), this, this,
-                                              m_method, m_url);
+void XMLHttpRequest::contextDestroyed(ExecutionContext* context) {
+  InspectorInstrumentation::detachClientRequest(context, this);
   m_progressEventThrottle->stop();
   internalAbort();
 
   // In case we are in the middle of send() function, unset the send flag to
   // stop the operation.
   m_sendFlag = false;
 }
 
 bool XMLHttpRequest::hasPendingActivity() const {
   // Neither this object nor the JavaScript wrapper should be deleted while
@@ skipping 34 matching lines @@
   visitor->traceWrappers(m_responseDocument);
   visitor->traceWrappers(m_responseArrayBuffer);
   XMLHttpRequestEventTarget::traceWrappers(visitor);
 }
 
 std::ostream& operator<<(std::ostream& ostream, const XMLHttpRequest* xhr) {
   return ostream << "XMLHttpRequest " << static_cast<const void*>(xhr);
 }
 
 }  // namespace blink